Since the publication of my last contribution on the Massachusetts Cocciæ, in 1899, no iess than 34 other species have been found to inhabit Mass., some of which appear to be of recent introduction and new to the United States; and while the larger portion has been recorded from other States, we have found several interesting new species hitherto not known to science. I have abandoned in part the citation of the geographical distribution and many of their food-plants, as time will not permit me to consult some of the literature. I have included an additional check-list and the Bibliography. In the original check-list several species are listed whose names have since been changed as follows.